Mattress pads are used to cover bed mattresses for several reasons. One is to keep the bed mattress clean. Another is to improve the feel or softness of the mattress. Most mattress pads in the past have been made of quilted ticking using fillers of various types, such as down, feathers, wool, natural or synthetic fibers and natural or synthetic foam rubber. While these mattress covers have worked reasonably well, some variations have been proposed to meet certain perceived needs.
An example of this is shown in U.S. Pat. No. 5,092,006 issued to Fogel, where an additional insulating pad is used in a waterbed application in addition to an ordinary mattress ticking cover. A problem with waterbed mattresses is that the water in the waterbed bladder acts as a heat sink. This can be uncomfortably cold to sleep on, so extra insulation is thought to be necessary or heaters must be used to keep the water warm. Most insulating pads for waterbeds have employed foam rubber layers to give the desired insulating effect. The Fogel patent, however, shows the use of an extra pad with metalized polyethylene film as an insulating layer in addition to foam layers. A difficulty with this extra pad in the Fogel construction, however, is that the foam rubber makes the pad non-washable. A mattress pad or cover for a mattress needs to be able to be laundered or washed, for obvious reasons. Further, the metalized film causes a condensation problem which results in mildew and odors, so the metalized film is actually undesirable.
The extra insulation needed for waterbed mattresses heretofore has not been thought to be necessary for conventional non-waterbed mattresses, because ordinary mattresses do not feel cold to the user. An insulating mattress cover has been used on an ordinary mattress in the past, however, but for a different purpose. U.S. Pat. No. 2,801,427 issued to Crocker shows a cover to make the mattress fireproof. It has a central aluminum foil sheet sandwiched between glass fiber mineral wool layers. Outer waterproof layers cover the glass fiber layers to make the pad waterproof and readily cleanable. A difficulty with the Crocker mattress pad, however, is that moisture or condensation will form on the surfaces of the pad making the sheets and bedding feel damp and clammy and also cause a mildew and odor problem. In addition, the aluminum foil in Crocker would make the pad very noisy to sleep on. Unless fireproofing is considered to be necessary, the Crocker mattress cover would actually be undesirable for ordinary mattresses.
Surprisingly, the present inventors have found that a metalized film can be used in a mattress cover without a moisture buildup problem and still produce a cover which is washable and not noisy to sleep on.